Sony CXA2570N Datasheet

RF Matrix Amplifier

Description

The CXA2570N is an IC developed for the RF signal

processing of compact disc players.

Features

• Wide band RF signal processing

• RF system VCA circuit

• RF system equalizer (supports CAV mode)

• Supports pickups with built-in RF summing amplifier

• Low power consumption mode (EQ Pass mode)

• RW/ROM switching mode

Functions

• RFAC summing amplifier, equalizer, VCA

• RFDC summing amplifier

• Focus error amplifier

• Tracking error amplifier

• Automatic power control

• VC buffer amplifier

Applications

CD-ROM/RW compatible systems

Structure

Bipolar silicon monolithic IC

Absolute Maximum ratings

• Supply voltage Vcc 7 V

• Operating temperature Topr –20 to +75 °C

• Storage temperature Tstg –65 to +150 °C

• Allowable power dissipation

PD 620 mW

Operating Conditions

• Supply voltage Vcc – GND 3.0 to 5.5 V

• Operating temperature Topr –20 to +75 °C

– 1 –

E98259A98-PS

Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by
any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the
operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits.

CXA2570N

24 pin SSOP (Plastic)

– 2 –

CXA2570N

Connected Circuit Diagram

VC

RF

VC

A

A

B
C
D

A
B
C
D

A
B
C
D

AC

SUM

DC

SUM

VC

B

VC

VC

FE

FE

FEI

100k

VC

C

VC

D

VC

F F

E

F
E

VC

E

RFDCI

RFAC

RFAC

RFDCO

RFDC

5.1k

VC

ACG

RW/ROM RW/ROM

RW/ROM

RW/ROM

Rfc Vfc

5.1k
<DSP>

<OP (with RF_SUM)>

EQIACSUM BST

V

CC

VCC

VCC

TE

TE

GND

V

CC

0.1µ

AC

VCA

EQ

APC

VC

VC

RW/ROM

RW/ROM

PD

LD

SW

10k

10k

APC-OFF (Hi-Z)

RW/ROM
(H/L)

VCVCC GND

VCC

VCC

VCC

VC

A

A
B
C
D

A
B
C
D

AC

SUM

DC

SUM

VC

B

VC

VC

FE

FE

FEI

100k

VC

C

VC

D

VC

F F

E

F
E

VC

E

RFDCI

RFAC

RFAC

RFDCO

RFDC

5.1k

VC

ACG

RW/ROM RW/ROM

RW/ROM

RW/ROM

Rfc Vfc

5.1k
<DSP>

<OP (without RF_SUM)>

EQI

ACSUM

BST

V

CC

VCC

TE

TE

GND

0.1

AC

VCA

EQ

APC

VC

VC

RW/ROM

RW/ROM

PD

LD

SW

10k

10k

APC-OFF (Hi-Z)

RW/ROM
(H/L)

VC GNDVCC

VCC

– 3 –

CXA2570N

Pin Description

Pin
No.

1
2
3
4
5
6
7
8

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

LD
PD
EQ_IN
AC_SUM
GND
A
B
C
D
E
F
SW
RFAC
FE
FEI
TE
VCC
RFG
BST
VFC
RFC
VC
RFDCO
RFDCI

Out

In
In

Out

In
In
In
In
In
In
In

In
Out
Out

—

Out

In

In

In

In

In
Out
Out

—

APC amplifier output.
APC amplifier input.
RFAC system VCA block and EQ block input.
RFAC system RF SUM output.
Ground.
A signal input.
B signal input.
C signal input.
D signal input.
E signal input.
F signal input.
Mode switching signal input.
RFAC signal output.
Focus error signal output.
FE amplifier virtual ground.
Tracking error signal output.
VCC.
RFAC system VCA block low-frequency gain adjustment.
EQ boost amount adjustment range.
EQ cut-off frequency adjustment.
EQ cut-off frequency adjustment.
VC voltage output.
RFDC signal output.
RFDC amplifier virtual ground.

Symbol I/O Description

– 4 –

CXA2570N

Pin Description and Equivalent Circuit

Pin
No.

1

2

3

4

5

O

I

I

O

— —

APC amplifier output.

APC amplifier input.

Equalizer circuit input.

RFAC summing amplifier
output.

Ground.

LD

PD

EQ_IN

AC_SUM

GND

Symbol I/O Equivalent circuit Description

10k

1k

1

20k

55k

20k

2

VCVC

1.2k

5k5k

1.1k1.1k

3

1.6k

1.6k

4

– 5 –

CXA2570N

Pin

No.

6 I

RF summing amplifier and
focus error amplifier input.

A

7 IB

8 IC

9 ID

10 I

Tracking error amplifier input.

E

11 I

Tracking error amplifier output.

F

16 OTE

CD-ROM/RW switching input.
RW when connected to VCC,
ROM when connected to
GND.

12ISW

RFAC amplifier output.

13ORFAC

Symbol I/O Equivalent circuit Description

VC

47k

47k

15k

7

30k

100µA

100µA

100µA

100µA

6

8

9

27k 27k

124

10

11

16

200k

12

200k

200k

100

2mA

13

Focus error amplifier output.

Focus error amplifier gain
adjustment. The gain is
adjusted by the external
resistance value connected
between this pin and Pin 14.

14

15

O

FE

IFEI

VC

50k

124

15

124

14

– 6 –

CXA2570N

Pin
No.

17 — —

Power supply.

VCC

Symbol I/O Equivalent circuit Description

18

I

Sets the RFAC low-frequency
gain.

RFG

100µA

VC

20k

18

19

I

Input for adjusting the
equalizer circuit boost amount.

BST

20k

50µA

VC

19

20

I

Input for adjusting the
equalizer circuit boost
frequency with the control
voltage.

VFC

100µA

VC

20k

20

21

I

Input for adjusting the
equalizer circuit boost
frequency with external
resistance.

RFC

124

1.0V

21

22

O

(VCC + GND)/2 voltage output.

VC

23

O

RFDC amplifier output. This
pin serves as the eye pattern
check point.

RFDC

24

I

RFDC amplifier gain
adjustment. The gain is
adjusted by the external
resistance value connected
between this pin and Pin 23.

RFDCI

25

150k

150k

22

124

VC

1mA

1.5k

124

23

24